Magma V2.15-9 Patch Notes

Function Fields¶

• A bug with sets of rational function field elements (where the hashing was wrong sometimes) has been fixed. Reported by M. Grassl.

Groups¶

• The missing irreducible subgroups of GL(2,2) in the IrreducibleMatrixGroup function have been found. Bug reported by C. Roney-Dougal.
• Improved algorithms for computing the soluble radical of matrix groups over the integers and rationals have been included.
• A faster method for computing ComplementEquationsMatrix for a module over the rationals has been adopted.
• The functions RWSGroup and RWSMonoid have been stopped from leaving an empty file in the /tmp directory at each call. Bug reported by S. Humphries and D. Holt.

Invariant Rings¶

• A bug in FundamentalInvariants for invariant rings of matrix groups which were not monomial has been fixed. Reported by M. Grassl.
• A crash in HomogeneousModuleTestBasis, when given zero polynomials, has been fixed. Reported by M. Grassl.

Lattices¶

• A crash when taking an ActionGenerator of a G-Lattice has been fixed.

Modular Symbols¶

• The empty sequence may now be coerced into the space of modular symbols.

Polynomial Rings¶

• A bug in multivariate resultant over finite fields (arising in factorization of polynomials over function fields) has been fixed. Reported by N. Bruin.

Sparse Matrices¶

• A bug in ModularSolution, which would result in a crash whenever Lanczos was selected without also selecting verbose output, has been fixed. Reported by C. Diem.